aboutsummaryrefslogtreecommitdiff
path: root/arch/x86_64/kernel/early-quirks.c
blob: 68273bff58ccf251f1f83c5da27e4a71b8f97f5b (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
/* Various workarounds for chipset bugs.
   This code runs very early and can't use the regular PCI subsystem
   The entries are keyed to PCI bridges which usually identify chipsets
   uniquely.
   This is only for whole classes of chipsets with specific problems which
   need early invasive action (e.g. before the timers are initialized).
   Most PCI device specific workarounds can be done later and should be
   in standard PCI quirks
   Mainboard specific bugs should be handled by DMI entries.
   CPU specific bugs in setup.c */

#include <linux/pci.h>
#include <linux/acpi.h>
#include <linux/pci_ids.h>
#include <asm/pci-direct.h>
#include <asm/proto.h>
#include <asm/dma.h>

static void via_bugs(void)
{
#ifdef CONFIG_IOMMU
	if ((end_pfn > MAX_DMA32_PFN ||  force_iommu) &&
	    !iommu_aperture_allowed) {
		printk(KERN_INFO
  "Looks like a VIA chipset. Disabling IOMMU. Override with iommu=allowed\n");
		iommu_aperture_disabled = 1;
	}
#endif
}

#ifdef CONFIG_ACPI

static int nvidia_hpet_detected __initdata;

static int __init nvidia_hpet_check(unsigned long phys, unsigned long size)
{
	nvidia_hpet_detected = 1;
	return 0;
}
#endif

static void nvidia_bugs(void)
{
#ifdef CONFIG_ACPI
	/*
	 * All timer overrides on Nvidia are
	 * wrong unless HPET is enabled.
	 * Unfortunately that's not true on many Asus boards.
	 * We don't know yet how to detect this automatically, but
	 * at least allow a command line override.
	 */
	if (acpi_use_timer_override)
		return;

	nvidia_hpet_detected = 0;
	acpi_table_parse(ACPI_HPET, nvidia_hpet_check);
	if (nvidia_hpet_detected == 0) {
		acpi_skip_timer_override = 1;
		printk(KERN_INFO "Nvidia board "
		       "detected. Ignoring ACPI "
		       "timer override.\n");
		printk(KERN_INFO "If you got timer trouble "
			"try acpi_use_timer_override\n");
	}
#endif
	/* RED-PEN skip them on mptables too? */

}

static void ati_bugs(void)
{
	if (timer_over_8254 == 1) {
		timer_over_8254 = 0;
		printk(KERN_INFO
	 	"ATI board detected. Disabling timer routing over 8254.\n");
	}
}

struct chipset {
	u16 vendor;
	void (*f)(void);
};

static struct chipset early_qrk[] = {
	{ PCI_VENDOR_ID_NVIDIA, nvidia_bugs },
	{ PCI_VENDOR_ID_VIA, via_bugs },
	{ PCI_VENDOR_ID_ATI, ati_bugs },
	{}
};

void __init early_quirks(void)
{
	int num, slot, func;

	if (!early_pci_allowed())
		return;

	/* Poor man's PCI discovery */
	for (num = 0; num < 32; num++) {
		for (slot = 0; slot < 32; slot++) {
			for (func = 0; func < 8; func++) {
				u32 class;
				u32 vendor;
				u8 type;
				int i;
				class = read_pci_config(num,slot,func,
							PCI_CLASS_REVISION);
				if (class == 0xffffffff)
					break;

		       		if ((class >> 16) != PCI_CLASS_BRIDGE_PCI)
					continue;

				vendor = read_pci_config(num, slot, func,
							 PCI_VENDOR_ID);
				vendor &= 0xffff;

				for (i = 0; early_qrk[i].f; i++)
					if (early_qrk[i].vendor == vendor) {
						early_qrk[i].f();
						return;
					}

				type = read_pci_config_byte(num, slot, func,
							    PCI_HEADER_TYPE);
				if (!(type & 0x80))
					break;
			}
		}
	}
}